/*
 * jQuery pager plugin
 * Version 1.0 (12/22/2008)
 * @requires jQuery v1.2.6 or later
 *
 * Example at: http://jonpauldavies.github.com/JQuery/Pager/PagerDemo.html
 *
 * Copyright (c) 2008-2009 Jon Paul Davies
 * Dual licensed under the MIT and GPL licenses:
 * http://www.opensource.org/licenses/mit-license.php
 * http://www.gnu.org/licenses/gpl.html
 * 
 * Read the related blog post and contact the author at http://www.j-dee.com/2008/12/22/jquery-pager-plugin/
 *
 * This version is far from perfect and doesn't manage it's own state, therefore contributions are more than welcome!
 *
 * Usage: .pager({ pagenumber: 1, pagecount: 15, buttonClickCallback: PagerClickTest });
 *
 * Where pagenumber is the visible page number
 *       pagecount is the total number of pages to display
 *       buttonClickCallback is the method to fire when a pager button is clicked.
 *
 * buttonClickCallback signiture is PagerClickTest = function(pageclickednumber) 
 * Where pageclickednumber is the number of the page clicked in the control.
 *
 * The included Pager.CSS file is a dependancy but can obviously tweaked to your wishes
 * Tested in IE6 IE7 Firefox & Safari. Any browser strangeness, please report.
 */
(function($) {

 $.fn.pager = function(options) {

 var opts = $.extend({}, $.fn.pager.defaults, options);

 return this.each(function() {

     // empty out the destination element and then render out the pager with the supplied options
     $(this).empty().append(renderpager(parseInt(options.pagenumber), parseInt(options.pagecount), options.buttonClickCallback));

     // specify correct cursor activity
     $('.pages li').mouseover(function() { document.body.style.cursor = "pointer"; }).mouseout(function() { document.body.style.cursor = "auto"; });
     });
 };

 // render and return the pager with the supplied options
 function renderpager(pagenumber, pagecount, buttonClickCallback) {

 // setup $pager to hold render
 var $pager = $('<ul class="pages"></ul>');

 // add in the previous and next buttons
 $pager.append(renderButton('first', pagenumber, pagecount, buttonClickCallback)).append(renderButton('prev', pagenumber, pagecount, buttonClickCallback));

 // pager currently only handles 10 viewable pages ( could be easily parameterized, maybe in next version ) so handle edge cases
 var startPoint = 1;
 var endPoint = 9;

 if (pagenumber > 4) {
     startPoint = pagenumber - 4;
     endPoint = pagenumber + 4;
 }

 if (endPoint > pagecount) {
     startPoint = pagecount - 8;
     endPoint = pagecount;
 }

 if (startPoint < 1) {
     startPoint = 1;
 }

 // loop thru visible pages and render buttons
 for (var page = startPoint; page <= endPoint; page++) {

     var currentButton = $('<li class="page-number">' + (page) + '</li>');

     page == pagenumber ? currentButton.addClass('pgCurrent') : currentButton.click(function() { buttonClickCallback(this.firstChild.data); });
     currentButton.appendTo($pager);
 }

 // render in the next and last buttons before returning the whole rendered control back.
 $pager.append(renderButton('next', pagenumber, pagecount, buttonClickCallback)).append(renderButton('last', pagenumber, pagecount, buttonClickCallback));

 return $pager;
 }

 // renders and returns a 'specialized' button, ie 'next', 'previous' etc. rather than a page number button
 function renderButton(buttonLabel, pagenumber, pagecount, buttonClickCallback) {

     var $Button = $('<li class="pgNext">' + buttonLabel + '</li>');

     var destPage = 1;

     // work out destination page for required button type
     switch (buttonLabel) {
         case "first":
             destPage = 1;
         break;
         case "prev":
             destPage = pagenumber - 1;
         break;
         case "next":
             destPage = pagenumber + 1;
         break;
         case "last":
             destPage = pagecount;
         break;
     }

     // disable and 'grey' out buttons if not needed.
     if (buttonLabel == "first" || buttonLabel == "prev") {
         pagenumber <= 1 ? $Button.addClass('pgEmpty') : $Button.click(function() { buttonClickCallback(destPage); });
     }
     else {
         pagenumber >= pagecount ? $Button.addClass('pgEmpty') : $Button.click(function() { buttonClickCallback(destPage); });
     }

     return $Button;
 }

 // pager defaults. hardly worth bothering with in this case but used as placeholder for expansion in the next version
 $.fn.pager.defaults = {
pagenumber: 1,
            pagecount: 1
 };

})(jQuery);
